Yeah that's for sure. I'm feeling that pain now. I ended up mounting the ECU inside the car. I wanted to get under the battery but I don't want to give up the vacuum canister for the headlights and I really don't like drilling holes in the engine bay Same issue with the wires here. I'm going to depin and install the correct length wires. I don't like splices. Currently doing the research to order correct parts. What type of wire did you use for yours? 20 gauge TXL?? I know the power wires are 12. Have to make them new too.
I spent a LOT of time trying to track down all the correct wiring and terminals. Holley does list some wiring stuff on their website but not nearly enough to build a new harness just ordering from them. I haven't looked recently so maybe they updated their offerings.
I found a lot of what I needed from here;
https://www.eficonnection.com/ They sell pre-cut lengths of TXL wire. Was a good place to order from. I think I used Del City too.
I can't remember exactly where I found it but somewhere in the Sniper instructions there is a list of the wire gauges for the provided harness. I ended up making my own list using that as a template because I was so far away from what comes in the box. Obvious, bolded notes included.
To compound my problems while installing the Sniper, I was in the midst of re-wiring my entire car with an aftermarket wiring kit. My goal with both harnesses was to eliminate any extra wire and to integrate everything to make it all work like it was designed that way. Only so much you can eliminate from each. The 10-pin ECU connector is pretty useless unless you have A/C or electric fans which I don't. So basically there's this large, unused connector just laying there coiled up at the back of my intake. I hate stuff like that. Anyway...
Please don't take my list here as gospel. I don't know if I ended up using everything exactly because there were a couple things I had to re-do and may have wound up using different terminals or wire. Do your own homework but the list should at least give you a place to start.
Again, I'm not kidding when I say that I replaced every single wire in the useless, Holley supplied harness - not one, not 10, ALL of it. Maybe their product development team should think of a way to provide a non-terminated kit for the non-Chevy DIY types. Just a thought.
FYI, the 8 digit part numbers are from EFI connection.
Terminals
For main harness red 12ga. wire fuse holder connector
12033997 Metri-Pack 630 Series “pull to seat” Female Terminal, 12-10 ga.
7 pin female connector from TB to 40A 5 Pole fuel pump relay -
12084200 Metri-Pack 150 Series Female Terminal, 22-20 Ga.
20g Switched 12v Ignition Wire pink,
20g fuel pump relay trigger wire blue
20 ga. Pink Wire = 12V Switched - Should be
connected to a switched +12 volt power source. Power source
should only be active when the ignition is on. Make sure source
has power when engine is cranking.
12 ga. Red Wire = Battery Positive –
Connect directly to the battery post. This powers the Sniper EFI system.
12. ga Black Wire = Battery Negative –
Connects directly to battery negative post.
20 ga. Blue Wire =
+12v Fuel Pump Relay Power Output -
Used to directly power the fuel pump (max current 15A). Make sure to terminate blue wire properly if not utilizing blue wire to provide power to the fuel pump.
For fuel pump relay female terminals
Delphi 12015865 Metri-Pack 630 Series Female Terminal with tang, 22-20 GA
Delphi 12084588-L Metri-Pack 630 Series Female Terminal with tang
16 ga. Pink wire from 3 way connector to switched 12v power
12g Main Battery Power Wire red
12g Main Battery Ground Wire black
20g Crank Signal Positive Wire purple
20g Crank Signal Negative Wire green
Cable seals
Blue seal 15324974, 12048087 for 1.70-1.29 mm wire
for 20 ga. Red switched 12v ignition box wire,
fuel pump relay to 7 pin connector blue & pink wires
Dark Red seal 15324973, 12048086 for 2.85-2.03 mm wire
for 16ga. pink switched 12v distributor wire
Can bus gauge module white w. blk. stripe signal wire pin
TYCO # 3-1447221-3